We want to study further the mechanism whereby gold thioglucose and mercury thioglucose produce interruptions in the circulation of the hypothalamus. We want to do a comparative analysis of the feeding patterns of rats with ventromedial hypothalamic lesions, genetically obese rats, obese hyperglycemic mice (ob/ob) and obese diabetic mice (db/db). We want to examine also the patterns of self selection of protein fat and carbohydrates in these animals, as well as compare the degree of finickyness in these different kinds of obese animals. We want to examine the effect of 2-DG administered in various ways on patterns of food intake. We want to determine whether thresholds for the detection of electrical stimulation of the lateral hypothalamus vary as a function of the nutritional state of the animal.